1. Field of the Invention
The invention relates to a cable window winder particularly for installation in vehicles. Such winding devices generally consist of at least one guide rail with a slide element guided therein and connectable with the window pane, at least two holding angles connected to the guide rail and each supporting a guide pulley, and a fastening device for fitting the cable window winder.
2. Background Information
Normally considerable cable forces arise at the guide pulleys of a cable window winder which can lead to considerable leverages or bending moments, depending on the position of the fastening points of the cable window winder relative to the bearing points of the guide pulleys.
From DE 36 15 578 C1 a device is known for raising and lowering a vehicle window which has four stationary guide pulleys embraced by a closed cable which passes through a motion drive and is connected to holders fixed on the window pane. The known device is mounted on a guide frame which supports all the components of the device and has guide stays connected by cross supports and provided with guide grooves for guiding the holders which are connected to the cable pulley.
This known device furthermore has two separate cable loops driven by a common drive wheel so that should one cable loop tear then the device can still be operated in an emergency by the other cable loop. A disadvantage here however is that the guide frame of this device needs to have large dimensions in order to be able to take up the cable forces which occur without premature signs of wear, particularly as a result of the considerably large distances between its fastening points and the bearing points of the guide pulleys. This results in the known device having a heavy inherent weight.
Furthermore it has been usual up until now to provide the fastening points of a cable window winder in the guide rails or on holding angles or base plates attached thereto wherein the holding angles also support the guide pulleys and are then mounted at the ends of the guide rails (cf: DE 36 38 059 C2, DE 37 40 579 A1).
The known devices however all require more or less large dimensions for the components used since the rotational axes of the guide pulleys are always mounted at a distance from the fastening points of the devices. Also the attachment of holding angles which serve only for fixing the cable window winder and are usually connected by welded connections with the guide rails, incurs high manufacturing expense with correspondingly high production costs.